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300iq's blog

By 300iq, 4 years ago, In English

Hello Codeforces!

I became a coordinator of CodeChef Lunchtimes, and we are in need of high-quality proposals.

We hope to get rid of the 'CodeChef has low-quality problems' label.

So we would be grateful if you can provide a problem set that will work fine for the IOI-style contest! (Note that your problems should not necessarily follow the IOI syllabus).

You can read about compensation and the required difficulty of problems here.

Proposals for Lunchtimes should be submitted to the following e-mail: [email protected]

P.S. If you have hard problems for CodeChef Long Challenges, you can send them here

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4 years ago, # |
  Vote: I like it -162 Vote: I do not like it

my girlfriend broke up with me and now she's ghosting me?? what do i do?

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4 years ago, # |
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So finally you want IOI-style problems or problems for your three type of contest!??

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    4 years ago, # ^ |
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    What do you mean? IOI-style just means that problems should have subtasks.

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      4 years ago, # ^ |
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      problems of type 9, doesnt have subtasks and they are in Long contests(ig), but you've said you want IOI-style problems, i thought maybe you only need these problems for special contest or something like that. (btw ive never participated in any codechef contests so i was confused)

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4 years ago, # |
  Vote: I like it +432 Vote: I do not like it

RIP Codeforces 2010-2020

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4 years ago, # |
  Vote: I like it -169 Vote: I do not like it

Codechef should learn one thing, money can't buy everything, there is reason why Indians use forces more than chef.

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    4 years ago, # ^ |
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    Don't you know in codeforces also, people are paid to write contests?

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4 years ago, # |
  Vote: I like it +105 Vote: I do not like it

Oh no... How dare you ruin my impression that Codechef's problems are really bad?! Damn you, Ildar.

But honestly, I am really looking forward to seeing you change this platform.

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    4 years ago, # ^ |
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    Nice trick! :ursmart:

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      4 years ago, # ^ |
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      What's the trick?

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        4 years ago, # ^ |
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        no one will downvote him because he said the codechef in trash and he hope to see change at the same time!!

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          4 years ago, # ^ |
            Vote: I like it +44 Vote: I do not like it

          I don't think he intended to do that. You are over-analyzing, just like my English teacher.

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4 years ago, # |
  Vote: I like it +33 Vote: I do not like it

The page you linked still says that, for Lunchtime contests, "The syllabus is strictly restricted to IOI."

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    4 years ago, # ^ |
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    Yeah, it was intended to be like that when Lunchtimes were born, but nowadays this restriction is waived.

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4 years ago, # |
  Vote: I like it -21 Vote: I do not like it

All the best 300iq. BIGFAN HERE

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4 years ago, # |
Rev. 3   Vote: I like it -57 Vote: I do not like it

Some of the areas where I think codechef should improve

1)First of all the way it shows our answer is correct.On codeforces,when it comes in green color [Accepted] and when it comes on codechef [green color showing all subtasks have passed], it changes our mind and i can't express my feeling exactly in words,but i basically don't practise on codechef [or practise less] beacuse of this reason. Ya, I know it's a kind of bad thing not looking at problems,and looking on such silly things, but deep inside,I think it matters and when we ask someone why don't you code on codechef they just say "level of problems" [actually i also say this to some of my frnds], but somewhere the reason it also that green color.

2)Secondly, lets say if someone is solving a problem,then codeforces show that how many testcases have passed or how many pretests have passed, but codechef doesn't shows this, it just show red color or the green one.Even if someone is failing on the sample testcases, then also codechef doesn't shows that sample answer is wrong [Although i know its coders responsibility to check and run on sample testcases],but that small thing also affects our behaiviour towards codechef,and then when it comes why don't you code on codechef,we don't actually explain this all ,we simply say "level of problems".

3)Other reasons are just the way it displays problems and the testcases, and one thing why the problem is displayed on the left side of the screen and not in the centre and the right side panel is just for the submissions,why isn't the problem and the testcases given the centre alignment like codeforces.And again when it comes to why don't you code on codechef we just say .................

So that's all i want to mention,and these are my reasons,what i think personally,I know that building a platform like codechef requires a lot of hardwork, but this is what i think and therefore uses codechef less. I know i should just enjoy the problems and should not bother about such things,but when it comes to work on a nicely organized platform and platform [I am just talking about the way the codechef pages appear,don't take it wrong way],I prefer to work and spend time on the first one.

One thing i don't like about codeforces is that sometimes questions are not given ratings in a proper manner ,means sometimes they are underrated or overrated, but then also when it comes to practise, i normally type codeforces.com because there are a lot of things [actually everything] which i love about it.

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    4 years ago, # ^ |
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    I didn't get your first point. CodeForces shows green and CodeChef shows green, what is wrong with that? Could you explain in a simpler way?

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      4 years ago, # ^ |
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      I mean it comes it green color [Accepted] ---> it looks awesome

      but in codechef it just shows in light green color subtasks 1 is passed,subtasks 2 and so on.

      what i mean is its not as attractive as codeforces.

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        4 years ago, # ^ |
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        [I dont think you want more green than this](Capture.png)

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    4 years ago, # ^ |
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    be mature stop comparing this silly things green vs less green or whatever.

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4 years ago, # |
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Hey! Thanks for taking up this role.

Can we now expect more, and better quality subtasks in each problem? As far as I know, IOI problems tend to have at least ~5 or more subtasks, but most lunchtime problems have about 2.

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    4 years ago, # ^ |
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    I believe they have an "unwritten" rule that each problem should have just $$$1$$$ subtask worth $$$50$$$ points to make the scoring uniform. I doubt that people at CodeChef even care about the subtask quality since they're barely able to get the actual problems in time.

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4 years ago, # |
  Vote: I like it +12 Vote: I do not like it

Please Change the UI look as well as problem quality because codechef looks is rather distracting and very ancient, whereas Codeforces UI look is quite gorgeous.

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    4 years ago, # ^ |
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    I guess it's the opposite.

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    4 years ago, # ^ |
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    I love codeforces, but the UI is not 'gorgeous'

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      4 years ago, # ^ |
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      Just wondering. Which cp sites are then better from the ui point of view?

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        4 years ago, # ^ |
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        CSAcademy is the best, most other sites other than CF have better looking UIs since they're filled with less options everywhere

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        4 years ago, # ^ |
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        I feel that AtCoder is neat, but there isn't a discussion forum there.

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          4 years ago, # ^ |
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          That's what I feel too. Atcoder is quite decent, but it is missing a lot of convenient features. Also overall it seems somewhat cheap, because it is just plain bootstrap. Not like it matters much. Though it is easier to get used to it than codeforces because its design is way simplier

          Codechef is terrible. Participated in a couple of contests, ui was not enjoyable in the slightest. Topcoder is far beyond being just terrible

          So from my experience, codeforces is really the best

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      4 years ago, # ^ |
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      I like CF UI. It looks professional and clean while not being overly minimalistic.

      IMO many websites try too hard to have a very "modern" look but it just ends up looking cheap and kinda ugly. Many websites look like iPad apps but computers are not tablets and UI decisions need not be the same. I especially heavily dislike some fancy animated websites with title "React App" that don't even work half the time. Normal HTML+CSS is much nicer, let JS be a scripting language.

      And IMO an indirect reason CodeChef and TopCoder UIs suck is that they try to be fancy but can not pull it off.

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        4 years ago, # ^ |
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        Google was clean Yahoo was not. Internet Explorer had many toolbars, then came chrome. a clean and simple look is better.

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4 years ago, # |
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Not only quality of problems but codechef has to change it's whole format to compete with codeforces. 10 days for a contest is too much of time. There are only 2 official short contests in a month.

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    4 years ago, # ^ |
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    As long as the contest offers actually interesting problems that requires something like 5 hours of thinking and 2-3 hours of implementation rather than think for 5 minutes and then code for 3 days (say something like the problems that use generating functions, but with a greater variety of algorithms), I wholeheartedly support a contest that last 10 days.

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      4 years ago, # ^ |
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      I feel Codechef is slow as compared to Codeforces in many ways. There should be quality + pace of learning.

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        4 years ago, # ^ |
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        It's indeed slower, but if the contests are genuinely good it would worth it (see Atcoder/Topcoder for example). OC, the problem is that Codechef's problems are often of very poor or poor quality and their website not exactly user-friendly, but with Ildar being a coordinator, we can hope for some changes in the future.

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4 years ago, # |
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I've sent a problem idea a year and a half ago. No response :/

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4 years ago, # |
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People who are saying codechef has low quality problems are probably very out-dated (especially if they mean the problems offered in short contests too). I mean they got this impression many years ago and never gave codechef a second chance.

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    4 years ago, # ^ |
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    To be fair, I recently gave Codechef another chance in the August Cook-Off, and one of the problems was the exact same as a CSAcademy problem (both statements even used red and blue, lol).

    However, I think 300iq becoming coordinator will improve the quality tremendously. Great decision by Codechef, and I'll definitely continue to compete because of it.

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      4 years ago, # ^ |
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      This is different from what I meant.

      the issue of repeated problem in general is really difficult to avoid because the only perfect way to avoid it is by having contest admin who knows all problems on the internet. I mean when a contest admin receive a proposal of interesting problem idea and he hasn't seen it before then it's natural to approve and use it in a contest. Surely the contest admin who have seen more problems on the internet will do a better job at avoiding this issue.

      What I meant in my first comment is that some people think that it's a habit of codechef to just offer standard/repeated problems or problems which require zero thinking and heavy coding, it's been very long time that this is no longer the case in codechef.

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        4 years ago, # ^ |
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        I think you are right !! codechef has good problems, especially related to mathematics. Not until I read the blog , my initial impression was codeforces is borrowing mathematical problems from codechef, lol.

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        4 years ago, # ^ |
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        Both are equally good and should learn from each other. :)

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        4 years ago, # ^ |
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        I also had the same mindset about codechef, but for the last 3-4 months i have only been giving short contests and i feel the quality of questions especially in Div 1 has greatly improved other than some exceptional cases. Though I strongly feel that quality of servers can be improved and frequency of short contests can be increased.

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        4 years ago, # ^ |
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        So ultimately you are saying that codechef admin sucks,right ?

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4 years ago, # |
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If 300iq will be coordinator of lunchtime. Will he leave his duties involving codeforces?

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4 years ago, # |
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I just wish CodeChef increases the frequency of short contests. It's a pain to wait a month for the next contest. But yeah, of course, quality comes first.

Recent memory, screwed up in Cook-off, thought would do good at lunchtime, missed lunchtime by accident, had to painfully wait 30 days for the next contest.

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4 years ago, # |
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To all people suggesting increasing the frequency of contests: what about Codechef first establishes the quality, then increases the quantity?

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    4 years ago, # ^ |
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    To the point CodeChef_admin, 300iq please consider this first

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    4 years ago, # ^ |
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    With all due respect, CC is having much better contests than CF these days. Have a look at some previous longs/cookoffs/lunchtimes. Problems in CC actually involve algorithms and good logic, whereas in my opinion, CF problems especially A,B,C (Div 3,2) are largely based on observational skills and maths (constructive).

    However, this is just my opinion, and others may of course disagree.

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      4 years ago, # ^ |
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      The issue here is that many authors treat low-rated problems (i.e. Div 2 A-C) as perfunctory, so the problems don't have much thought put into them. Another thing is that there are only so many ways one can write problems for grey->cyan coders, as they normally can't do many things beyond the basic math, greedy and dp, so you really can't pull something very creative. ofc, you mostly do these low-rated problems so I can't really blame you for thinking this.

      CF has many interesting problems though, you just need to look higher up the rating scale. On the other hand, I feel like many CC problems are very implementation-based (e.g. most of the DS problems, which take no thought and 200+ lines of implementation). In my opinion though, the best place to go for interesting problems is AtCoder, which mostly has really light implementation but require a lot of thought.

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4 years ago, # |
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We hope to get rid of the 'CodeChef has low-quality problems' label.

On codechef, it's not easy to know whether a contest is an official (high-quality) or not (no guarantee of quality). Actually, I judge it from only my experience (cook-off, lunchtime, and challenge are official). Is there another easy way?

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    4 years ago, # ^ |
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    With my experience you can identify if the contest is rated or not. Rated contest are more legit as compared to non-rated ones. Plus there are many college contests as well, I generally go by the prizes as that kind of ensures that organizing team has put some efforts in the preparation.

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      4 years ago, # ^ |
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      So, how can people know whether a contest is rated or not?

      (IMO, the prize doesn't ensure that. Here is an example from a recent contest. All of 3 problem statement was super unclear, and nobody understands the 3rd problem after all.)

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        4 years ago, # ^ |
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        For the rated contest except the ones you mentioned, Cook off, Lunchtime and Long they mention along with the contest name. For eg {name}(Rated for all/Div2) . And yes not all contests that have prizes are legit but they have a decent probability of being good. Club with a reliable organisation and it becomes more reliable, like many organisations conduct some sort of annual coding contests and for such contests there is a codeforces blog for the same.

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          4 years ago, # ^ |
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          except the ones you mentioned, Cook-off, Lunchtime, and Long

          I'm talking about the official contests, and these ARE official contests :(